If a fig tree is not getting enough water, the leaves will turn yellow and drop.

If a fig tree is getting too much water, the leaves will turn yellow and drop.

If a fig tree is getting too much sun, the leaves will turn yellow and drop.....

All three statements are on the web.    So how do you know whether a potted fig is starving for water, or drowing and rotting?    Starved for light, or burning.  

Aside from reckless guesswork and if it doesn't die you're right, or teaching your plant to talk.... are there any foolproof indicators of these?

Because yes, a couple days after potting, my fig tree's lower leaves are yellowing and one dropped :/

A cheap moisture meter can help you with the moisture levels of a container if you have difficulty noticing the signs (weight, drooping, fingering the soil, etc).

    For example: 
    https://jet.com/product/LUSTER-LEAF-PRODUCTS-1810-RAPITEST-MINI-MOISTURE-METER/8505c063fbbb40398aa274c1c988507f

Too much sun probably isn't an issue unless you moved it from inside or a shady location into full sun or live in a very hot / sunny climate.  Might want to update your signature with your zone/location.

Figs will sometimes drop a couple of older lower leaves without any cause for concern.  Pics can help.

Oh, and sips work great for worry free watering.  Just keep the reservoir topped up.

Sips sound fantastic.   Do you have anything you recommend? 

If I knew some really good reliable signs, I'd sure be watching.   So far the web says, if the leaves turn yellow and fall, then its either overwatered or underwatered.  Drooping also means not enough, and too much water I've learned from experience.    Pot weight might help but its a pretty heavy pot.

I've tried a moisture meter in years past with little success.   I still killed the plant.   Though I did great with clay water Nannys.  I don't think they would work for a tree sized plant though.    This plant is also outside, so it will get rain.

I'm in Zone 5b.  I'm pretty sure the browning was heat shock as the delivered plant was still in its bag in the driveway, with the sun directly on it.   Its since been put in a large pot where its roots should stay cooler I'm sure.

Still I've heard that young figs shouldn't be in direct sun.   But then you hear everything online.  It would be a pity though to come home and find it roasted.

I'm thinking its one day late for a sip, now that I've read up on them a bit.   I already spent $90 on the large tree pots, drilled holes in the bottoms and have potted the plants yesterday.   Its looking like that would be scrapping all and starting over.

Would that I had known this earlier.   Well, hindsight is 20/20.

Check out this Tree Nanny - "Jingle Bells when it needs water".   Too bad it got poor reviews:

https://www.amazon.com/Tree-Nanny-Christmas-Watering-Device/dp/B004C7S6P8

It could be as simple as a large saucer underneath.  Give it enough water to take a day or two to soak up.  Leave the saucer empty for a day and repeat.

I put a layer of rocks in the bottom of the pots, an old habit someone in the family taught me that years ago no idea if it does any good.   Supposedly helps with drainage.

The trees are outside so they get will rain like all the other trees out there, and what's more it will surely pool and run through as the pot edges are about an inch or two higher than the soil.

But if I put the pots in saucers, would that not have the roots in 'standing water', the big no-no that kills figs?   Also as the drain holes are on the bottom, any excess water from rain would collect in and not drain out.

I have @50 trees. They all get soaked every AM unless it has rained or is going to be very overcast and cool. Some of the recently up potted ones may get a topping off instead of a soaking. It has been a real hot, dry summer and I cant imagine over watering would be a problem unless the pot is sitting in a saucer full of water for extended periods. Sometimes at the end of a hot breezy day, some of them may be wilted . They get water right away and again the following AM. I know my watering schedule goes against some of the recommendations but my plants are all thriving and full of fruit.The only time that i have had problems with over watering has been in the early stages when dealing with newly rooted cuttings.

I have about 6 Hibiscus trees in my backyard, and two I grew from seed in pots, which took months.   It just so happened the weeks after they finally made it to the yard we had a freak drought with 95+ degree temps.  It just would not rain.   I took to a bucket of water on each tree once day, as they would wilt and then come back after watering.   So far so good.

However, at some point, they wilted and water would no longer revive them.   So, I watered more, going by the adage, "I can't imagine over watering would be a problem in this heat".    They finally just plain died.   My strong suspicion is root rot from overwatering, but you'll notice the symptoms of overwatering and underwatering were practically identical.

Sure doesn't make it easy....

That layer of rocks probably rules out the saucer as well.

I believe that most have determined that a drainage layer isn't generally helpful and simply raises the water table higher in the container but opinions will vary as with everything.

Standing water in the bottom of a saucer with figs hasn't been an issue for me and they grow much better that way.  I wouldn't leave them in a pool of water that covers the container but half an inch or two at the bottom isn't an issue.  Water gets soaked up as needed without drowning the tree.  I have some trees in 2 liters that need up potted sitting in a kiddie pool with 1/2" of water almost constantly in it.  I try to make sure that it dries up at least once a week but that is more to prevent mosquitoes than for the figs.  Fig cuttings are sensitive to about everything but they grow out of it.    Figs trees love wet feet in containers.  In ground may be different.  I haven't been able to drown one yet and I have a heavy hand watering.

Even when it rains I generally have to water my 5 gallon containers unless it rains a lot over a long period.  Those big leaves do a great job of shedding water away from the containers.

If I were you, I'd watch for drooping and use a finger to test.  If they are drooping and it is wet, hold off on water and look for other reasons.  Some varieties like VDB seem to droop on hot sunny days even when properly watered.  If the top feels dry even if they aren't drooping, water.